1. Field of the Invention
The present invention relates to a frame structure of a construction machine such as a bulldozer or the like.
2. Background Information
In a conventional construction machine such as a bulldozer or the like, a boat-shaped main frame has various components mounted thereon, such as a slant nose, a track frame, a tank frame, a cab, and the like.
For example, Patent Document 1 discloses a main frame structure for a construction machine in which a pair of left and right main frames are constructed with a single thin straight plate disposed along the longitudinal direction of a vehicle, hollow pillar members are fixed to the left and right outer surfaces thereof, and the positions of the column members are in substantially the same plane as the position of a cross member that pivotably supports an equalizer bar.
[Patent Document 1]
Japanese Utility Model Application Publication 2000-027229 (published Jan. 25, 2000)
[Patent Document 2]
Japanese Utility Model Application Publication H06-049284 (published Jul. 5, 1994)
[Patent Document 3]
Japanese Patent Application Publication H02-088877 (published Jul. 13, 1990)
However, the conventional frame structure for a construction machine described above has the following problems.
In other words, with the frame structure of the construction machine disclosed in the aforementioned patent applications, it cannot be assumed that a cab having a rollover protective structure (ROPS) is mounted thereon. Because of this, it will be necessary to ensure that there is space to dispose the necessary mount units, stopper units, or the like on the individual main frames when a cab having a ROPS is to be mounted thereon.
An object of the present invention is to provide a frame structure of a construction machine that can ensure the necessary space on the frame in order to mount a cab having a rollover protective structure and thereby strengthen the construction machine.